Central-shank-reaming disk bit



May 3, 1927. F w' HlLD CENTRAL SHANK mzzmame Dlsx BIT Filed Nov. a. 1924 Patented May 3, 1927.

FREDERIC W. HILI), OF LOS ANGELES, CALIFORNIA.

1c E. g

CENTRAL-SHANK-REAMIN G DISK BIT. l.

l Application led November 8, 1924. Serial No. 748,565.

This invention relates to bits, and it relates particularly to rotary disk-bits which are used in the drilling of oil wells.

A well is drilled by means of a drill bit secured to the lower end of a drill pipe. The drill pipe is arranged to be rotated by a rotary table situated at the surface of the well, this being effective in rotating the bit and sinking the hole. Rotary disk bits, to which this invention closely pertains, are used extensivel in preference to the fishtail types of bit,\th1s being because disk bits are ot' a much longer life than ishtail bits. The long life of disk bits is due to the fact that the disks thereof may rotate on their own axes as the complete bit rotates. Substantially one-fourth of the perimetric cutting edge of the disks is working at one time, so that it may naturally be assumed that the cutting edge will last much longer in this type of disk than the cutting edge of other types of bit.

These disk bits, however, have their disadvantages.

In the first place, diicnlty is present because of the inability (in the present designs) to provide rugged enough bearing members for the disks.= Logicall ,this inability in `creases the danger :of lt e losing of a disk due to the breakage of a bearing pin, or the bending of bearing pins which may impede the working progress of the bit, and necessitates elevating 1t to the surface to replace the damaged parts, thus consuming much time and being expensive.

Itis an object of this invention to overcome the above deficiency in the present types of disk bit by provlding a bitv which is so designed as to ermit the use of very rugged bearing or dis supporting members.

It is another object of this invention to provide a unique means for retaining the earing members in place, this retaming means being so constructed and so situated that external impediments cannot dislodge or loosen it.

Another disadvantage of the present t pes of disk bit is the tendency thereof to ore corkscrew or crooked holes, the undesirableness of a crooked or corkscrew hole being obvious as it places a preponderance of strain on thek drill pipe and bit, necessitates reaming, and makes it difficult to ,install a well casing. The corkscrewingofa bit-of this character may have its source in the of disk bits is the forming of cores. Since thel disks are spaced apart from each other a relatively substantial distance, it is obvious that -the'lnaterial between the disks is not subjected to the cutting action thereof. A cent1-al core, therefore, forms as the bit progresses downwardly. The core will soon encounter the central support and in hard formations may prevent further progress of the bit. In-any case, a rising core may deflect the bit and cause a crooked hole.

It is a still further object of this invention to provide a means for cutting away the core as it forms and in this manner provide 'a diskA bit in which thereis less danger of drilling a crooked hole. p

It is another object of this invention to provide a disk bit having. in combination a means for reaming the hole to proper size.

It is a still further object of this invention -to provide in a disk bit of the character described means for insuring rotation of the reaming means or elements on their own axis.

Other objects and advantages of the invention will appear in the following description.

Referring to the drawings which are for illustrative purposes onl Fig. 1 isanelevationa view of a disk bit embodying the features of my invention, this view being sectioned near the lower por; tion thereof to facilitate the showingy of the improved form of` bearing members and the novel means employed for securely retaining the bearing members in place.

Fig. 2 is ,an elevational view taken atri ht angles to Fi 1, a small portion thereof eing sectione to clearly show the construction of the reaming elements of the bit.

Fig. 3 is a section taken substantially as indicated by the line 3--3 of Fig. 2.

Fig. 4 is a section taken substantially as indicated by the line 4 4 of Fig. 1.

Fig. 5 is a bottom plan view of Fig. 1..

this View clearly showing the position of the core-removing means emplo ed `in conjunction with other features of t e bit.

In the drawingsthe numeral 11 represents the body of the bit, this body being comprised of a shank portion 12 having a threaded pin 13 at the upper end thereof for securing the bit to the lower end of a string of drill pipe. Formed adjacent and below the shank portion 12 is a central portion 14, from which there depends a central lower leg 15. n

The boring means provided in this invention may consist of bearing members 17 and 18 which have cylindrical bearing portions 19 which are flattened at 20, as clearly shown in Fig. 4, there being formed at theouter end of the bearing portions 17 and 18 head portions 21. The bearing members 17 and 18 are each, as shown in Fig. 4, arranged to be inserted in an opening 23 in the depending leg 15, these pins being inserted from opposite sides ofthe leg 15 and being posi tioned so that the flattened faces 2O thereof are in contact with each other. Rotatably disposed on the extending portions ot' the bearing surfaces 17 an i8 are boring disks 25 and 26, which are s1tuated between the heads 21 and wear plates 28. -v The bearing.

members are arranged to be secured in place by means of a central locking pin 30 which extends into an axial opening 31, provided in the central depending leg 15. In the contacting faces 2() of the bearing members 17 and 18 there are formed semi-circular grooves 252 which when the pins are installed, as shown in Fig. 4, co-operate to provide a circular opening 33 through which the locking pin 3() extends and serves to lock themembers 17 and 18 against movement in any direction. The locking p in 3() is al rangedvto be held in place in the axial opening 3l by means of a threaded portion 34 which threads into the lower end of the depending leg 15, as is clearly shown iirFig. l. By the construction illustrated, it is-possible to provide much larger bearing surfaces than is possible in any of the previous types of disk bit. It is also possible to place the centers of the bits in approximate alignment, thereby permitting the use of fairly large disks.

Reamiug and aligning means provided by the invention may be in the form of bearing members 4() and 4l,- having semi-cylindi-irai portions 42 whiclrare flattened as shown at 43 in Fig. 3, these cylindrical portions being inserted in the opening 44 provided in the central portion 14 of the body ll in such a manner that the llat faces 42S are in contact with. each other. The bearing members 40 and 4l are extended into the opening 44 in the central portion 14 from opposite sides thereof, similar to the bearing members 17 and 18, but substantially at right angles to Leanne the bearing members 17 and 18. Formed at the outer end of the cylindrical portions 42 are bearing portions 46 which extend outward and upward, as clearly shown in Fig. 2, so as to be non-perpendicular to the axis of rotation of the bit A-A (Fig. 2). 4At the outer` endsof the bearing portions 46 there are provided cylindrical heads 47. In the flat portions 43there are provided semicircular grooves 48 which cooperate to provide a cylindrical opening 49, through which the extreme upper end of the locking pin 30 extends. In this manner, the locking pin 3() is made to lock both the boring bearing members 17 and 1 8 and the reaming bearing members 40 and 41 in place. Rotatably on the bearing portions 46 are reaming members in the form of disks 51, which are situated between the heads 47 and wear receiving Washers 52.

By inspection of Fig. 2, it will be seen that, due to the presence of the slant in the bearing portions 4G, the`reaming disks 51 will be made to lie non-perpendicular to the axis ot' rotation A-A. In other words, the reaming disks 51 converge relative to each other at the upper portions thereof. It will be seen that this construction allows rugged bearing members large bearing surfaces and large disks, as does the construction employed for supporting the boring disks. By utilizing a unitary means for securing both the boring and the reaming bearing members in place, it is possible to provide a disk bit having fewer parts, thus allowing more rugged construction and providing ay device which is much simpler to assemble than the present bits. Rotation of the reaming disks is assured by the disposal of these disks in nonsparallel aligmnent to each other and'to the axis of rotation A--A.

The reaming disks are placed at right angles since such disks, when in contact with only the side of the hole, do not rotate and tlat places form thereon which are obviously disadvantageous. The tractive effort of' the disk to rotate on its own axis depends upon the angular relationship of the disk with respect to the surface against which it cuts or rides. When .aforce is applied tothe periphery ofa disk at right angles to the extension of the axis thereof, or, in other words, in a tangential direction, the rotative tendency thereof is at its maximum. When the force is applied against the periphery of a disk yin the same direction as the extension of the axis ot' the disk, the rotative tendency incurred in the disk is Jat its minimum.- From the drawing it will be seen that force exerted against vthe periphery of the reaming disk 51 is appliedin a direction which is perpendicular to the axis of rotation A-A of the bit. It will be seen that were the disks mounted perpendicular to the axis A-A, the rotative4 tendency would be nothing. However, by mounting the disks at an angle relative to the axis AA, the rotative tendency is magnified according to the angle.

On the head portion 60 of the securing pin 30 cutting blades 61 may be formed, these cutting blades being a means for removing or cutting away a core, indicated at 62, as it forms, so that no interference to the progress of the drill will be encountered. It will be seen that the friction againstthese blades produces a tendency to tighten the threads 34 of the pin 30 and, therefore', assures that the members 40 and 41 will not be dislodged. It will be seen that as the blades wear away 'they may be readily and easily re-sharpened because of the possibility of removing the complete pin 30. When the blades wear sufiiciently to justify replacement, this may be cheaply done because ot' the simple and inexpensive design of the locking pin 30.

Lubricating fluid may be supplied through a central lubricating passage 64 which branches at 65 to avoid the bearing members 40 and 41 and has openings 67 for supplying fluid to the boring disks 25 and 26. Lubricating mud may be supplied ,to the core cutting member through the opening 68 inthe secured pin 30.

From the foregoing description, it will readily be seen that the breaking and dislodging of the bearing members is avoided by the provision of much more rugged bearing members and much more extensive bearing surfaces (han is possible in the previous types of drill bits. l can do this because of the provision of the novel type of bearing members and the novel type of securing means. The locking pin 30 is protected against external impediments by the in' ternal positioning thereof. The only external contact of the member 30 is at the cutters (il, which contact ltends lto tighten the member- 30 in place.

rlhe corkscrewing and wobbling of the drill is prevented by the supplying .of the novel guiding means in the form of reaming disks 51. From the drawings it will be seen that the reaming disks are disposed substantially at right angles to the boring disks and, therefore,'provide contact with the wall of the hole in four places around the circumference thereof. Although Ihave shown only one series of reaming disks, it is manifest that several series, one series above the other, might be disposed around the body l2 at varying angles so as to contact with correspondingly more wall of the hole and in more places on the circumference thereof. v

Any interference to the progression of the drill, due to the formation of cores, is 'entirely eliminated bythe provision of the /1.A. disk bit comprising: a body having a central portion and a depending leg; lower bearing members carried by said depending leg; boring disks rotatably supported on said lower bearing members; upper bearing members carried by said central portion; reaming disks carried by said upper bearing members; and unitary means for retaining both said lower and upper bearing' members in place.

2. A. disk bit comprising: a body having a central portion and a depending leg; lower bearing members carried by said depending leg; boring disks rotatably supported on said lower bearing members; upper'bearing members carried by said central portion; reaming disks carried by said upper bearing members; and a securing in extending into said body" and contactlng with' said lower and upper bearing members for securing said lower and upper bearing members in place.

3. A diskbit as defined in claim 2 in which the lower end of said securing pin has core-removing blades formed thereon.

4. A disk bit as defined in claim 2 in which said securing pin has a threaded portion at the lower end which screwsinto said body for retaining said securingV pin in place and has core-removing cutters formed on the lower end thereof.

5. In a bit, the combination of: a body adapted to carry `a. plurality of' rotatable disk cutters; means' supported by said body for carrying said disks; and a locking key insertable along the longitudinal axis of said body engaging said means so as to retain said means Land said disks to said body, said locking key having cutting blades at one end. y

6. A disk bit comprising; a body having a vcentral portion and a depending leg; lower bearing members carried by said depending leg; boring disks rotatably supported on said lower bearing members; upper bearing members carried by saidcentral portion; reaming disks carried by said upper bearing members; and unitary means extending axially'into said body for retaining both said upper andlower bearing mem.- bers in lace.

7'. A isk bit comprising: a body having a central portion and a depending leg; lower bearing members carried by said depending leg; boring disks rotatably supported on said lower bearing members; upper bearing members carried by said central portion; reaming disks carried by said upper bearing members; and a securing pin inserted axially into said body and being threadably secured in place, said pin being arranged to secure both said lower and upper bearing members in place.

8. A disk bit comprising: a body having a central portion and a depending leg, there 'being a lubricating 'passage extending through said central portion; upper bearing members extending into sald eentral portion, said lubricating passage being so formed as to extend around said upper bearing members; lower bearing members extending into said depending leg; upper disks carried by said upper bearing members; lower disks carried b said lower bearing members; and a securing pin for retaining said upper and lower bearing members in place, said securing pin having a passage therein which connects with said lubricating passage.

ln testimony whereof, I have hereunto set my hand at Los Angeles, California, this lstday of November, 1924.

FREDERIC W. Il ILD. 

